RESUMEN
The efficacy of human recombinant osteogenic protein-1 (OP-1; bone morphogenetic protein-7) in regeneration of dog larynx was examined by treating thyroid cartilage defects (1.5 cm2) in dogs with thyroid allografts covered with host perichondrium or fascia. Prior to implantation allografts were frozen, thawed and demineralized. The treatment groups were as follows: I--Allograft control implant (n = 3); II--Implants coated with 500 micrograms OP-1 (n = 4); III--Implants coated with 100 micrograms OP-1 (n = 3); IV--Implants coated with 500 micrograms OP-1 and covered with neck fascia (n = 3); and V--Implants extracted with 1 M NaCl and guanidine hydrochloride, and coated with 500 micrograms OP-1 (n = 4). Dogs were sacrificed four months following surgery. Each larynx was removed, carefully dissected and a three-dimensional reconstruction of the defect area was performed on serial sections. The results revealed that the implants of control dogs remained intact with no apparent reduction in size and new tissue formation. OP-1 enriched thyroid allografts, dose dependently induced bone, cartilage and ligament-like structures comprising up to 80% of the total regenerated defect area. Boundaries of the defects healed by formation of new bone when bone resided within the old thyroid cartilage layers. Old cartilage not containing bone within its layers healed by complete integration with newly formed cartilage. Both new bone and cartilage were embedded into layers of new ligament-like tissue which expressed specific morphologic and molecular markers. The three newly formed tissues were tightly connected into a "bone-cartilage-ligament continuum" of tissues, suggesting that OP-1 served as a multiple tissue morphogen in this specific microenvironment.
Asunto(s)
Proteínas Morfogenéticas Óseas/farmacología , Regeneración Ósea/efectos de los fármacos , Cartílago Tiroides/crecimiento & desarrollo , Factor de Crecimiento Transformador beta , Animales , Proteína Morfogenética Ósea 7 , Proteínas Morfogenéticas Óseas/administración & dosificación , Perros , Fascia/fisiología , Humanos , Cuello , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Trasplante HomólogoRESUMEN
Due to high frequency, certain risk of related complications, absenteeism, direct and indirect costs related to them, acute respiratory infections represent a significant health problem. The aim of the paper is to examine the frequency and characteristics of acute respiratory infections, as well as the characteristics of patients with these infections among the population in care of general practitioners/family physicians. In 11 teaching general practices in Zagreb, data were collected from medical records on patients and acute respiratory infections which the patients developed over the period from October 1, 1994 to September 30, 1995. For statistical data processing description, distribution analysis and chi-square test were used. Out of 17,888 patients in care of general practitioners involved in the study, acute respiratory infections were noticed in 4,114 (22.9%) patients ranging in age from newborn to 97 years out of which 1,473 (35.8%) were males and 2,641 (64.2%) were females. A total of 5,892 acute respiratory infections were observed, in average 1.43 infections per patient, for which the patients visited their general practitioners 11,610 times (1.97 visits per infection). Most of the patients 2,958 (71.9%) attended their general practitioners because of one acute respiratory infection. The initial diagnosis of acute upper respiratory tract infection was registered in 4,601 (78.1%) infections, and final diagnosis in 4,475 (75.9%) infections. The most frequent diagnoses included: pharyngitis and tonsillitis (including streptococcal pharyngitis and tonsillitis), nasopharyngitis, sinusitis and bronchitis. In 4,874 (82.7%) cases, general practitioners based their diagnosis on patient history and clinical examination. Antibiotics were prescribed in 3,892 (66.1%) cases. Out of 42 (1.2%) patients treated in hospital, seven patients were admitted for tuberculosis and two for bronchi cancer detected during the acute respiratory infection. Follow-up was reported in 3,644 (60.3%) cases, and sick leave in 1,236 (31%) cases. The results of this study have shown significantly higher frequency of acute respiratory infections in the morbidity in outpatient health care, and also that management of patients with these diseases is mainly the responsibility of general practitioners. In order to improve professional competence of general practitioner/family physician and quality of work in the management of patients with acute respiratory infections in general practice/family medicine, it is necessary to continuously improve the knowledge on all characteristics of the management of patient with these diseases in general practice, as well as to make a critical assessment of the existing practice.